Field of the Invention
The present invention relates to a press machine and a method for controlling a slide of a press machine, and in particular, to a technology of forming a material while imparting microvibration to a mold.
Description of the Related Art
Conventionally, there has been proposed a vibration press-forming method in which a vibrator is connected to an upper mold of a press machine and a material is pressed between the upper mold and a lower mold by lowering the upper mold while ultrasonically vibrating it with the vibrator (Japanese Patent Application Laid-Open No. 01-122624).
Further, there have been proposed a vibration machining device which transmits vibration to a press head through a lever mechanism, and a press-forming device in which a vibration mechanism having a cam part is fitted at an intermediate rotational fulcrum of a link mechanism for driving a slide (Japanese Patent Applications Laid-Open No. 09-285896 and No. 2008-260042).
Moreover, there have been proposed press machines which apply vibration to a slide with a servomotor indirectly driving a crankshaft through a gear, etc. (Japanese Patent Applications Laid-Open No. 2011-16138 and No. 2011-245515), a press which directly applies vibration to a slide with a linear servomotor (Japanese Patent Application Laid-Open No. 11-77389), and a press machine which uses a servomotor to drive a slide through a screw-nut mechanism without involving a decelerator, wherein high-frequency vibration is applied to induce micromotion of the screw-nut mechanism (Japanese Patent Application Laid-Open No. 11-151631).